Polymerizable dental materials capable of being cured by exposure to high intensity light in a short time interval have become very popular. Commercially available photocurable materials are formulated to be cured by exposure to ultraviolet radiation in the spectral range between 300 to 400 nm and/or by exposure to visible light in the spectral range of between 400 to 500 nm. The light source is, in general, positioned as close to the point of application as is practical, so as to provide high intensity light directly to the restoration without the use of long fiber-optic light guides. This technique is currently used to deliver the maximum amount of optical power to the dental restorative material at the operatory site independently of the light assembly used
It has been discovered that by supplementing the source of light with a source of heat, the physical properties of light-cured dental resins can be enhanced. The supplemental heat can be applied either during or after the curing process It has also been demonstrated that the bond strength of the cured dental materials to adjacent tooth structure can be significantly increased by curing these materials with a combined application of heat and light, as well as diametral tensile strength and surface hardness. The apparatus of the present invention provides a source for generating light over a preselected spectral range to effect polymerization of the dental material, in combination with a controlled variable source of heat, in the form of hot air, for supplementing the light radiation with a supply of heat during the light curing process in order to enhance the physical properties of the dental material. The physical properties which are susceptible to the present invention include the surface hardness, diametral tensile strength, and the flexure strength, as well as the shear strength to tooth structure.